Paul urges the believers to be careful not to turn to the words and rules of others because nothing can add to the fullness of God that believers have in Christ.
Paul speaks of the way a person can believe false teachings (because they believe false things or love the wrong things) as if someone had physically caught and held that person by force. (See: [[rc://en/ta/man/translate/figs-metaphor]])
Paul speaks of false ideas that produce nothing and so are without value as though they are containers with nothing in them. (See: [[rc://en/ta/man/translate/figs-metaphor]])
The "tradition of men" may refer to Jewish traditions, while "the elemental spirits of the world" refers to pagan (Gentile) belief systems. Both of these are worthless.
Possible meanings are 1) this refers to spiritual powers that some people thought control what happens on earth, or 2) this refers to the laws or moral principles of the world.